Page 285 - Masonry and Concrete

Paving

284 CHAPTER EIGHT

8-5 to create a slanting riser face. If space is tight, this can help to
accommodate a deeper tread than might otherwise fit.
To measure the total rise and run for steps, use wooden stakes and
a string with a line level (Figure 8-6). Divide the total measured rise by
the desired riser height to get the number of risers required. Adjust the
length of the run as necessary to get the right tread depth for the riser
height being used. If space is limited, adjust the riser height and tread
depth proportionally until the steps fit within the available space.
Flights of three or more steps need a footing, and in cold climates the
footing should extend below the frost line for protection against frost
heave (Figure 8-7). Steps with more than five or six risers can be bro-
ken into two runs separated by a landing that is at least 3 ft. in the
direction of travel (Figure 8-8). For stepped ramps in sloping lawns,
follow the guidelines in Figure 8-9 for either single or paired risers.
Make each riser within a flight of steps the same height and each tread
the same depth so that people don’t trip.
Steps leading up to a door should have a landing at the top that is
at least 3 ft. 3 ft., but preferably larger for both safety and appear-
ance. Whether the approach is from the front or from the side, the min-

1 /2" RADIUS

TREAD DEPTH

OPTIONAL
SLANTED
RISER
RISER 1"
HEIGHT

RULE OF THUMB: 2R + T 25
(2 6) + 12 = 24
(2 5) + 14 = 24
(2 7) + 10 = 24
(2 7) + 11 = 25
(2 7 1 /2) + 10 = 25
FIGURE 8-5

Design of steps.

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